Don’t let your swimming pool get into this state before you repaint it!
I’m not a big fan of rental properties with swimming pools. They are something that many tenants love the idea of but don’t like to pay to maintain. There is a cost to use professional painters but it’s well worth it if you’re not fully prepared to deal with the process I’m about to explain. Getting it wrong can mean an expensive waste of time and costly materials, not to mention the inconvenience to the tenant. This isn’t something I would want to do myself and I would use a professional swimming pool painter every time!
Firstly, we are talking about concrete pools. Don’t go painting your fibreglass pool because you don’t like the colour. It won’t work!
Painted concrete swimming pools will fade over time. If the problem is only fading and there is no bubbling, cracking or chalky surface, then you may want to try a light acid wash to brighten the paint up. You can enquire about this at your pool shop.
If you have either of these problems, you’ll need to consider repainting the pool;
Bubbling
Your painted surface has failed and water is getting behind the paint to form bubbles. This is often caused by poor preparation of the surface and is another reason to use a professional!
Crackling
Old paint will naturally flake away but if you have long cracks in your paint, you might have bigger problems with subsidence and cracking in the concrete. Check to make sure there is no movement in the ground or water table problems. No point in painting this pool until you’re sure it’s stable!
Chalking
Painted surfaces will degrade after some time. If you can rub your fingers over a dry surface and they come away dusty, the paint is nearing the end of it’s lifespan.
What sort of paint to use
There are three options for pool paint; Epoxy, Rubber Base and Acrylic. Expoxy is the only one you should consider. It’s the longest lasting at 7-8 years, more durable and stands up well to UV rays, pool cleaners and chemicals. Rubber base paint is cheaper but only lasts 3-5 years. Acrylic paint is really for commercial pools that will be regularly re-painted and lasts only 2-3 years. This is not a job you want to do that often!
How to paint your swimming pool
If you’re painting a new pool, the concrete must be left to cure for at least a month. The surface then needs to be cleaned of any residual chemicals, dust, grease and other traces that will undermine the paint’s adhesion to the concrete. A roof wash is suitable for this job.
If the surface is too smooth, the paint won’t adhere properly. Prepare if by lightly blasting or grinding to improve adhesion.
- For pre-painted concrete pools, firstly, you need to check what sort of paint the pool is already coated with. Epoxy paint will not cover a rubber based paint.
- Once the pool has been fully drained and cleaned of any debris, start to remove all loose paint with a high pressure water blaster. Don’t use the electric ones in a pool! A petrol powered water blaster with at least 2000 psi of pressure should do the job.
- Remove any loose concrete. If the concrete is cracked, you need to dig them out to at least 5mm and caulk cracks and holes with hydraulic cement.
- An acid wash will remove all the remaining material and kill off any biological contaminants. Use 50% water and 50% muriatic acid or a solution recommended by your pool shop. Scrub the walls and floor thoroughly. Make sure you wear protective clothing and a suitable mask. Rinse the entire pool area.
- Now clean the entire pool with trisodium-phosphate or suitable alternative. This is a detergent that will neutralize the acid and remove the glaze from any remaining paint. Rinse again with fresh water and allow to dry for 3-5 days. You can check if the concrete is dry by taping the edges of a square of transparent plastic to the base of the pool. If there is no condensation after 24 hours, you’re good to go.
- Before painting, double check your surface and remove any remaining loose material. The paint will need to be very well mixed – allow 5 mins or more using a power mixer. Apply the paint with a short pile, solvent-resistant roller starting at the deep end and work your way to the shallow end. Having to phone a friend for rescue from the deep end is embarrassing! Apply a second coat after 4 hours. Avoid excessive rolling to prevent trapping bubbles in the paint.
Ideally, you want the paint the pool on a clear, fine day that is not too hot, too cold or too humid. Wait at least 4 days after completing for the paint to cure before filling the pool. If it rains during this time, you need to remove any standing water and add extra time for the paint to cure. After the paint has cured, fill the pool, restart the filter and add chemicals as required.
IMPORTANT: Make sure that you check with your pool shop and paint supplier for the best options. The above chemicals are only an indication of what can be used and are not necessarily going to be available in your area or what is best for your pool. Safety equipment is very important for this job, you’re working with solvents, acid and potentially dangerous old paint. Don’t take it lightly!
